Display device having a touch screen panel

ABSTRACT

A display device includes a first substrate, a second substrate, pads, and first and second flexible circuit boards. The first substrate includes a first insulating substrate, a first resistance layer formed on the first insulating substrate, and first and second signal lines formed on the first insulating substrate. The second substrate faces the first substrate and includes a second insulating substrate, a second resistance layer formed on the second insulating substrate, and third and fourth signal lines formed on the second insulating substrate. The pads comprise a first pad connected to the first signal line, a second pad connected to the second signal line, a third pad connected to the third signal line, and a fourth pad connected to the fourth signal line. The first flexible circuit board is connected to two of the pads and the second flexible circuit board is connected to the other two pads.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of co-pending U.S.application Ser. No. 11/936,253 filed Nov. 7, 2007, which claimspriority to Korean Patent Application No. 2006-0131913, filed on Dec.21, 2006, in the Korean Intellectual Property Office, the disclosureswhich are each hereby incorporated by reference in their entireties.

BACKGROUND OF INVENTION

1. Technical Field

The present disclosure relates to a display device, and moreparticularly, to a display device having a touch screen panel.

2. Discussion of the Related Art

An image display device may include a cathode ray tube (CRT), a liquidcrystal display (LCD), a plasma display panel (PDP), or an organic lightemitting diode (OLED). The image display device may further include aninput device such as a touch screen panel.

When a user presses a surface of the touch screen panel, for example,using a finger or a pen, information corresponding to a pressed positionis transferred to the image display device and displayed.

The touch screen panel includes signal lines for sensing the pressedposition. An electrical signal generated by the pressing may be outputexternally through a pad connected with a signal line.

However, pads can increase the size of the touch screen panel, therebyincreasing the size of the display device. Thus, there is a need for adisplay device with a touch screen panel that has a reduced size.

SUMMARY OF THE INVENTION

An exemplary embodiment of the present invention provides a displaydevice including a first substrate, a second substrate, pads, a firstflexible circuit board, and a second flexible circuit board. The firstsubstrate includes a first insulating substrate, a first resistancelayer formed on the first insulating substrate, and first and secondsignal lines formed on the first insulating substrate. The secondsubstrate faces the first substrate and includes a second insulatingsubstrate, a second resistance layer formed on the second insulatingsubstrate, and third and fourth signal lines formed on the secondinsulating substrate. The pads include a first pad connected to thefirst signal line, a second pad connected to the second signal line, athird pad connected to the third signal line, and a fourth pad connectedto the fourth signal line. The first flexible circuit board is connectedto two of the pads and the second flexible circuit board connected tothe other two pads.

The first flexible circuit board and the second flexible circuit boardmay be connected to different corners of the first substrate,respectively.

The pads may be formed on the first substrate, and the display devicemay further include a conducting member which is formed between thefirst and second substrates and electrically connects the third pad withthe third signal line and the fourth pad with the fourth signal line,respectively.

The first flexible circuit board may be connected to one of the firstand second pads and to one of the third and fourth pads.

The first and second pads may be formed on the first substrate, thethird and fourth pads may be formed on the second substrate, and thefirst and second flexible circuit boards may be provided as a doublesided circuit board.

The display device may further include a liquid crystal panel placed inback of the first substrate.

The first insulating substrate may include glass, and the secondinsulating substrate may include a polymer film.

The liquid crystal panel may include a first liquid crystal panelsubstrate formed with a thin film transistor, a second liquid crystalpanel substrate facing the first substrate and formed with a blackmatrix, and a liquid crystal layer positioned between the first andsecond liquid crystal panel substrates, wherein the pads are positionedwithin an area of the black matrix.

The display device may further include a liquid crystal panel substratefacing a rear surface of the first insulating substrate, and formed witha thin film transistor, and a liquid crystal layer positioned betweenthe first insulating substrate and the liquid crystal panel substrate.

The display device may further include a black matrix formed on the rearsurface of the first insulating substrate, wherein the pads arepositioned within an area of the black matrix.

The display device may further include a first polarizing platepositioned on a rear surface of the liquid crystal panel substrate, anda second polarizing plate positioned on an upper surface of the liquidcrystal panel substrate.

The second insulating substrate may include a polymer film.

An exemplary embodiment of the present invention provides a displaydevice that includes a first substrate, a second substrate, pads, and aflexible circuit board. The first substrate includes a first insulatingsubstrate, a first resistance layer formed on the first insulatingsubstrate, and a plurality of X signal lines formed on the firstinsulating substrate. The second substrate faces the first substrate andincludes a second insulating substrate, a second resistance layer formedon the second insulating substrate, and a plurality of Y signal linesformed on the second insulating substrate. The pads include a pluralityof sub-pads electrically connected to one of the X signal lines and theY signal lines, respectively. The flexible circuit board includes aflexible film, and a first input lead formed on a first surface of theflexible film and corresponding to a first set of the sub-pads.

The flexible circuit board may include a first flexible circuit boardand a second flexible circuit board which are connected to differentcorners of the first substrate, respectively.

The flexible circuit board may include a second input lead formed on asecond surface of the flexible film and corresponding to a second set ofthe sub-pads.

The first insulating substrate may include glass, the second insulatingsubstrate may include a polymer film, and the pads may be formed on thefirst insulating substrate.

The sub-pads electrically connected to the X signal line may be formedon the first substrate, and the sub-pads electrically connected to the Ysignal line may be formed on the second substrate.

The display device may further include a liquid crystal panel substratefacing a rear surface of the first insulating substrate and formed witha thin film transistor, and a liquid crystal layer positioned betweenthe first insulating substrate and the liquid crystal panel substrate.

The display device may further include a black matrix formed on the rearsurface of the first insulating substrate, wherein the pads arepositioned within an area of the black matrix.

The display device may further include a first polarizing platepositioned on a rear surface of the liquid crystal panel substrate, anda second polarizing plate positioned on an upper surface of the secondinsulating substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects of the present invention will become moreapparent by describing in detail exemplary embodiments thereof, withreference to the accompanying drawings, in which:

FIG. 1 is a high-level block diagram of a display device according to anexemplary embodiment of the present invention;

FIG. 2 is a perspective view of a display device, according to anexemplary embodiment of the present invention;

FIG. 3 is a cross sectional view, taken along line III-III of FIG. 2;

FIG. 4 is a magnified view of part A of FIG. 3;

FIG. 5 is a plan view of a first substrate of the display device of FIG.2, according to an exemplary embodiment of the present invention;

FIG. 6 is a plan view of a second substrate of the display device ofFIG. 2, according to an exemplary embodiment of the present invention;

FIG. 7 is a cross sectional view, taken along line VII-VII of FIG. 6;

FIG. 8 is a front view of a flexible circuit board of the display deviceof FIG. 2, according to an exemplary embodiment of the presentinvention;

FIG. 9 is a cross sectional view, taken along line IX-IX of FIG. 2;

FIG. 10 is a plan view of a first substrate of the display device ofFIG. 2, according to an exemplary embodiment of the present invention;

FIG. 11 is a plan view of a first substrate of the display device ofFIG. 2, according to an exemplary embodiment of the present invention;

FIG. 12 is a perspective view of a display device according to anexemplary embodiment of the present invention;

FIG. 13 is a cross sectional view, taken along line XIII-XIII of FIG.12;

FIG. 14 is a magnified view of part H of FIG. 13;

FIG. 15 is a plan view of a first substrate of the display device ofFIG. 12, according to an exemplary embodiment of the present invention;

FIG. 16 is a plan view of a second substrate of the display device ofFIG. 12, according to an exemplary embodiment of the present invention;

FIGS. 17A through 17C illustrate a flexible circuit board of a displaydevice of FIG. 12, according to an exemplary embodiment of the presentinvention;

FIG. 18 is a cross sectional view, taken along line XVIII-XVIII of FIG.12;

FIG. 19 is a plan view of a first substrate of the display device ofFIG. 12, according to an exemplary embodiment of the present invention;

FIG. 20 is a plan view of a second substrate of the display device ofFIG. 12;

FIG. 21 is a perspective view of a display device according to anexemplary embodiment of the present invention;

FIG. 22 is a plan view of a first substrate of the display device ofFIG. 21, according to an exemplary embodiment of the present invention;

FIG. 23 is a plan view of a second substrate of the display device ofFIG. 21, according to an exemplary embodiment of the present invention;

FIGS. 24A and 24B illustrate a flexible circuit board of the displaydevice of FIG. 21, according to an exemplary embodiment of the presentinvention; and

FIG. 25 is a cross sectional view, taken along line XXV-XXV of FIG. 21.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Hereinafter, exemplary embodiments of the present invention will now bedescribed more fully with reference to the accompanying drawings. Likereference numerals may refer to like elements throughout thespecification.

While the embodiments below illustrate, for example, that a displaydevice includes a touch screen panel and a liquid crystal panel, thepresent invention is not limited to a liquid crystal panel, and mayinstead include, for example, an organic light emitting diode (OLED), aplasma display panel (PDP), or an electrophoresis display device.

Referring to FIGS. 1 and 2, a display device 1 according to an exemplaryembodiment of the present invention includes a touch screen panel 100, aliquid crystal panel 200, a control unit 300, and a flexible circuitboard 400.

The touch screen panel 100 is positioned on the liquid crystal panel200, and a side part of the touch screen panel 100 is connected with theflexible circuit board 400. The flexible circuit board 400 includes afirst flexible circuit board 400 a and a second flexible circuit board400 b.

When a user presses the touch screen panel 100, for example, using afinger or a pen, an electrical signal is generated by the pressing. Thegenerated electrical signal is transferred to the control unit 300through the flexible circuit board 400. The control unit 300 analysesthe transferred electrical signal to calculate a coordinate of thepressed position, and displays information on the liquid crystal panel200 according to the calculated coordinate.

Referring to FIG. 3, the touch screen panel 100 includes a firstsubstrate 110, a second substrate 120, and an adhesive layer 140 forbonding together both substrates 110 and 120.

The liquid crystal panel 200 includes a first liquid crystal panelsubstrate 210, a second liquid crystal panel substrate 220, a sealant260 for bonding together both substrates 210 and 220, and a liquidcrystal layer 230 positioned within a space enclosed by both thesubstrates 210 and 220, and the sealant 260. A first black matrix 222 isformed along the sealant 260 in the second liquid crystal panel 220.

The touch screen panel 100 will be explained in detail with reference toFIGS. 4 through 7. Referring to FIGS. 4 and 5, the first substrate 110includes a first insulating substrate 111, an resistance layer 112formed on the first insulating substrate 111, a first signal line 113, asecond signal line 114, a first connecting line 115, and a secondconnecting line 116.

The first insulating substrate 111 may have an almost rectangular shape,and can be made of glass. An area of the first insulating substrate 111may be larger than the second insulating substrate 121. Pad areas B andC are disposed at a lower side of the first insulating substrate 111,which do not overlap with the second insulating substrate 121.

The first resistance layer 112 is formed substantially over an uppersurface of the first insulating substrate 111, and may be made of atransparent conductive material, such as, for example, indium tin oxide(ITO) or indium zinc oxide (IZO).

The first signal line 113 and the second signal line 114 face each otheracross the first resistance layer 112 therebetween, and extend along alongitudinal length of the first insulating substrate 111. Since thefirst signal line 113 and the second signal line 114 extend in the Xdirection, they are referred to as X signal lines. The first signal line113 and the second signal line 114 are electrically connected with eachother, and may be made of metal.

An end portion of the first signal line 113 forms a first pad 113 a, andthe first pad 113 a is not covered by the second substrate 120. An endportion of the second signal line 114 forms a second pad 114 a, and thesecond pad 114 a is not covered by the second substrate 120.

The first connecting line 115 is electrically connected with a thirdsignal line 123 of the second substrate 120, and formed along a lowerside of the first insulating substrate 111. The second connecting line116 is electrically connected with a fourth signal line 124 of thesecond substrate 120, and formed along an upper left side of the firstinsulating substrate 111.

An end portion of the first connecting line 115, which is close to thesecond pad 114 a, forms a third pad 115 a, and the third pad 115 a isnot covered by the second substrate 120. An end portion of the secondconnecting line 116, which is close to the first pad 113 a, forms afourth pad 116 a, and the fourth pad 116 a is not covered by the secondsubstrate 120.

The pads 113 a through 116 a may have an expanded width as compared tothe connected signal lines 113 and 114 and the connecting lines 115 and116. The pads 113 a through 116 a may be square shaped, with a length ofabout 1 mm.

The first pad 113 a and the fourth pad 116 a may be positioned withinthe first pad area B along the left bottom edge of the first insulatingsubstrate 111. The second pad 114 a and the third pad 115 a may bepositioned within the second pad area C along the right bottom edge ofthe first insulating substrate 111.

Referring to FIGS. 4 and 6, the second substrate 120 includes the secondinsulating substrate 121, a second resistance layer 122, the thirdsignal line 123, and the fourth signal line 124 formed on the secondinsulating substrate 121.

The second insulating substrate 121 may be made of polymer film, and mayhave a shorter length than that of the first insulating substrate 111.

The second resistance layer 122 is formed substantially over the lowersurface of the second insulating substrate 121, and may be made of atransparent conductive material, such as, for example, indium tin oxide(ITO) or indium zinc oxide (IZO).

The third signal line 123 and the fourth signal line 124 face each otheracross the second resistance layer 122 therebetween, and extend along ashorter length of the second insulating substrate 121. Since the thirdsignal line 123 and the fourth signal line 124 extend in the Ydirection, they are referred to as Y signal lines. The third signal line123 and the fourth signal line 124 are electrically connected with eachother, and may be made of metal.

Referring to FIG. 7, the fourth signal line 124 is electricallyconnected to the second connecting line 116 through a conducting member150, which may be made of metal. The conducting member 150 isdiscontinuously formed in the adhesive layer 140. The third signal line123 is electrically connected to the first connecting line 115 in asimilar manner.

A connection between the pads 113 a through 116 a and the flexiblecircuit board 400 will be described below with reference to FIGS. 8 and9. Referring to FIG. 8, the flexible circuit board 400 includes aflexible film 411, and a pair of connecting wires formed on the flexiblecircuit board 400.

A first connecting wire includes an input lead 421, an output lead 423,and a lead connecting portion 422 connecting both the leads 421 and 423.A second connecting wire includes an input lead 431, an output lead 433,and a lead connecting portion 432 connecting both the leads 431 and 433.

The first connecting wire and the second connecting wire are formed on asame surface of the flexible film 411. The input leads 421 and 431 areconnected with the pads 113 a through 116 a of the first substrate 110,and the output leads 423 and 433 are electrically connected to thecontrol unit 300.

The flexible circuit board 400 may further include an insulating filmcovering the lead connecting portions 422 and 432.

Referring to FIG. 9, the first pad 113 a and the fourth pad 116 a may beconnected to the first flexible circuit board 400 a. The first pad 113 ais electrically connected to the input lead 421 of the first connectingwire through an anisotropic conducting film 500, and the fourth pad 116a is electrically connected to the input lead 431 of the secondconnecting wire through the anisotropic conducting film 500.

The anisotropic conducting film 500 includes a base resin part 511 andconductive balls 512 scattered in the base resin part 511. Between thepads 113 a and 116 a and the input leads 421 and 431, the conductiveballs 512 forms an electrical channel by contacting with each other.

The second pad 114 a and the third pad 115 a may be connected to thesecond flexible circuit board 400 b in a manner similar to the first pad113 a and the fourth pad 116 a.

Spacers 130 are positioned on the first ohmic layer 112. The spacers 130may have a hemispheric shape, and protect both resistance layers 112 and122 from being short-circuited.

When the second insulating substrate 121 of the second substrate 120 ismade of a polymer film, it is likely to be deformed towards the firstsubstrate 110 due to gravity. If the second substrate 120 is deformed,both the resistance layers 112 and 122 may be shorted, thereby causing aproblem in sensing the pressed position. The spacers 130 protect bothresistance layers 112 and 122 from directly contacting with each othereven if the second substrate 120 is deformed.

The spacers 130 may be formed by, for example, screen printing, printingusing ultraviolet (UV) curing material or heat curing material.

The adhesive layer 140 is positioned along a perimeter of the touchscreen panel 100 and bonds together both substrates 110 and 120. Theadhesive layer 140 may be, for example, a double sided tape.

When the second substrate 120 is pressed, for example, using a pen or afinger to contact the first resistance layer 112 and the secondresistance layer 122 with each other, a resistance value is changedaccording to the contacted position.

Depending on the changed resistance value, current or voltage ischanged, and the changed current or voltage is outputted through thepads 113 a through 116 a and the flexible circuit board 400. The outputleads 423 and 433 of the flexible circuit board 400 may be connected tothe control unit 300 directly or a driving unit (not shown) of theliquid crystal panel 200.

The liquid crystal panel 200 will be further described with reference toFIGS. 2, 3 and 4.

The first liquid crystal panel substrate 210 includes a third insulatingsubstrate 211, thin film transistors 212, an insulating film 213, andpixel electrodes 214.

The third insulating substrate 211 may be made of, for example, glass orplastic. Each of the pixel electrodes 214 are electrically connected tothe respective thin film transistors 212.

The second liquid crystal panel substrate 220 may include a fourthinsulating substrate 221, the first black matrix 222, a second blackmatrix 223, a color filter 224, an overcoat layer 225, and a commonelectrode 226.

The fourth insulating substrate 221 may be made of, for example, glassor plastic. The second black matrix 223 is formed to correspond to thethin film transistor 212. The color filter 224 includes a plurality ofsub layers having different colors, for example, red, green, and blue.The common electrode 226 is formed across the fourth insulatingsubstrate 221.

The pixel electrodes 214 and the common electrode 226 may be made of atransparent conductive material such as, for example, indium tin oxide(ITO) or indium zinc oxide (IZO).

An electric field is formed between the pixel electrodes 214 and thecommon electrode 226. The electric field adjusts an arrangement of LCmolecules within the liquid crystal layer 230, thereby controlling thetransmittance of light.

A first polarizing plate 240 is attached on an outer surface of thefirst liquid crystal panel substrate 210. A second polarizing plate 250is attached on an outer surface of the second liquid crystal panelsubstrate 220.

The first polarizing plate 240 is attached to a rear surface of thethird insulating substrate 211 of the first liquid crystal panelsubstrate 210 using an adhesive (not shown). The first polarizing plate240 includes a polarizing layer controlling a polarization state ofincident light and a supporting layer positioned on a top surface and abottom surface of the polarizing layer.

The polarizing layer may be formed by heating a thin film of poly vinylalcohol (PVA), extending the heated film, and depositing iodine on theextended film.

The supporting layer may be made of, for example, triacetyl cellulose(TAC). The supporting layer may be used to prevent the extrudedpolarizing layer from shrinking and to protect/support the polarizinglayer.

Since the second polarizing plate 250 has a similar structure as thefirst polarizing plate 240, its description will be omitted.

The display device 1 may further include a backlight unit positioned inback of the liquid crystal panel 200.

The pads 113 a through 116 a of the touch screen panel 100 are dividedinto pairs and connected to the flexible circuit boards 400 a and 400 b.

Since each of the pad areas B and C are not complex, a width d1 neededfor a pad area formation can be reduced, thereby reducing the size ofthe touch screen panel 100.

The pad areas B and C, the signal lines 113, 114, 123, and 124, and theconnecting lines 115 and 116 may be positioned within the black matrix222 area of the liquid crystal panel 200.

An arrangement of the signal lines 113 and 114 and the connecting lines115 and 116 of the first substrate 110 may be changed in a variety ofways, as described in other embodiments.

Referring to FIG. 10 and FIG. 6, the third pad 115 a of the firstconnecting line 115 is connected with the third signal line 123, and isformed adjacent to the first pad 113 a.

The second connecting line 116 is connected with the fourth signal line124 and is elongated to extend along the second signal line 114 Thefourth pad 116 a is formed adjacent to the second pad 114 a.

The first pad 113 a and the third pad 115 a are positioned on a firstpad area D, which is positioned at a bottom left side of the firstinsulating substrate 111. The second pad 114 a and the fourth pad 116 aare positioned on a second pad area E, which is positioned at a bottomright side of the first insulating substrate 111.

The flexible circuit board 400 and the first substrate 110 are connectedin the same way as the first substrate 110 of FIG. 5. The first flexiblecircuit board 400 a is connected to the first pad 113 a and the thirdpad 115 a, and the second flexible circuit board 400 b is connected tothe second pad 114 a and the fourth pad 116 a.

Referring to FIG. 11, the third pad 115 a of the first connecting line115 is connected with the third signal line 123 and formed adjacent tothe first pad 113 a.

Further, the first pad 113 a and the third pad 115 a are formed towardsthe longitudinal length of the first insulating substrate 111.

The second connecting line 116 is connected with the fourth signal line124 and elongated to extend along the second signal line 114, and thefourth pad 116 a is formed adjacent to the second pad 114 a.

The first pad 113 a and the third pad 115 a are positioned on a firstpad area F, which is positioned at a bottom left side of the firstinsulating substrate 111. The second pad 114 a and the fourth pad 116 aare positioned on a second pad area G, which is positioned at a bottomright side of the first insulating substrate 111.

Additionally, the flexible circuit boards 400 a and 400 b are connectedwith a different side of the first insulating substrate 111,respectively. The first flexible circuit board 400 a, which is attachedto a longitudinal side of the first insulating substrate 111, isconnected with the first pad 113 a and the third pad 115 a, and thesecond flexible circuit board 400 b, which is attached to a shorter sideof the first insulating substrate 111, is connected with the second pad114 a and the fourth pad 116 a.

A display device according to an exemplary embodiment of the presentinvention will be described with reference to FIGS. 12 through 18.

Referring to FIGS. 12 through 14, the second liquid crystal panelsubstrate 220 of the liquid crystal panel 200 shares the firstinsulating substrate 111 with the first substrate 110 of the touchscreen panel 100. The first resistance layer 112 is formed on an uppersurface of the first insulating substrate 111. The black matrix 222, 223and the color filter 224 are formed on the bottom of the firstinsulating substrate 111.

The second polarizing plate 250 of the liquid crystal panel 200 isformed on an upper surface of the touch screen panel 100.

According to at least one embodiment of the present invention, a widthof the display device 1 can be shortened by reducing the use ofinsulating substrates. In addition, a weight of the display device 1 canbe reduced and a product cost can be saved.

The first substrate 110 will be described with reference to FIGS. 14 and15. The first substrate 110 includes a first insulating substrate 111, afirst resistance layer 112 formed on the first insulating substrate 111,a first signal line 113, and a second signal line 114. In thisembodiment, connecting lines are not formed on the first substrate 110.

The first resistance layer 112 is formed substantially over an uppersurface of the first insulating substrate 111, and may be made of atransparent conductive material such as, for example, indium tin oxide(ITO) or indium zinc oxide (IZO).

The first signal line 113 and the second signal line 114 face each otheracross the first resistance layer 112 therebetween, and extend along alongitudinal length of the first insulating substrate 111. The firstsignal line 113 and the second signal line 114 are electricallyconnected with the first resistance layer 112, and may be made of metal.

An end portion of the first signal line 113, which is adjacent to thebottom side of the first insulating substrate 111, forms a first pad 113a, and an end portion of the second signal line 114, which is adjacentto the bottom side of the first insulating substrate 111, forms a secondpad 114 a.

The second substrate 120 will be described with reference to FIGS. 14and 16. The second substrate 120 includes the second insulatingsubstrate 121, a second resistance layer 122, the third signal line 123,and the fourth signal line 124 formed on the second insulating substrate121.

Since the second polarizing plate 250 is positioned on the upper surfaceof the second insulating substrate 121, the second insulating substrate121 may be made of non-extending anisotropic polymer film, and may besubstantially similar in size to the first insulating substrate 111.

Alternately, the second resistance layer 122 may be formed on thesupporting layer of the second polarizing plate 250. When this occurs,the supporting layer forms the second insulating substrate 121.

The third signal line 123 is extended along a lower side of the secondinsulating substrate 121, and an end portion adjacent to a right side ofthe second insulating substrate 121 forms a third pad 123 a.

The fourth signal line 124 is extended along an upper left side of thesecond insulating substrate 121, and an end portion adjacent to a lowerside of the second insulating substrate 121 forms a fourth pad 124 a.

The first pad 113 a and the second pad 114 a are formed on the firstsubstrate 110, and the third pad 123 a and the fourth pad 124 a areformed on the second substrate 120.

The first pad 113 a and the fourth pad 124 a are positioned on a padarea I of a bottom left edge of the first insulating substrate 111 andarranged to face each other.

The second pad 114 a and the third pad 123 a are positioned on a padarea J of a bottom right edge of the first insulating substrate 111 andarranged to face each other.

Pairs of the pads 113 a, 114 a, 123 a, and 124 a are assembled togetherin both edges of the touch screen panel 100.

A connection between the pads 113 a, 115 a, 123 a, and 124 a and theflexible circuit board 400 will be described below with reference toFIGS. 17A through 17C and 18.

Referring to FIGS. 17A through 17C, the flexible circuit board 400includes a flexible film 411, and a pair of connecting wires formed onthe flexible film 411.

A first connecting wire includes an input lead 421, an output lead 423,and a lead connecting portion 422 connecting both the leads 421 and 423.A second connecting wire includes an input lead 431, an output lead 433,and a lead connecting portion 432 connecting both the leads 431 and 433.

The flexible circuit board 400 may be a double side flexible circuitboard. The input lead 421, the output lead 423, the lead connectingportion 422, and the output lead 433 are formed on a first surface 411 aof the flexible film 411, and the input lead 431 of the secondconnecting wire is formed on a second surface 411 b of the flexible film411.

A portion of the lead connecting portion 432 of the second connectingwire is connected to the output lead 433 and fanned on the first surface411 a. Further, the other portion of the lead connecting portion 432 isconnected to the input lead 431 and formed on the second surface 411 b.The portions of the lead connecting portion 432 formed on differentsurfaces 411 a and 411 b are connected with each other through a via 412formed on the flexible film 411.

Referring to FIG. 18, the first pad 113 a and the fourth pad 124 a areconnected to the first flexible circuit board 400 a. The first pad 113 ais electrically connected to the input lead 431 of the second connectingwire through an anisotropic conducting film 500, and the fourth pad 124a is electrically connected to the input lead 421 of the firstconnecting wire through the anisotropic conducting film 500.

The anisotropic conducting film 500 includes a base resin part 511 andconductive balls 512 scattered in the base resin part 511. Theconductive balls 512 form an electrical channel by contacting with eachother between the pads 113 a and 124 a and the input leads 421 and 431.

The second pad 114 a and the third pad 123 a are connected to the secondflexible circuit board 400 b in a manner similar to the way the firstpad 113 a and fourth pad 114 a are connected to the first flexiblecircuit board 400 a.

In FIG. 18, the liquid crystal panel 200 under the first insulatingsubstrate 111 is not shown.

In each pad area I and J, pairs of the pads 113 a and 123 a, and 114 and124 a may be positioned to overlap in a perpendicular direction witheach other, so that the required pad area is reduced, thereby reducingthe size of the touch screen panel 100.

The pad areas I and J are positioned within the area of the black matrix222. A width d2 of the black matrix 222 may be about 2 mm.

In addition, the arrangement of the signal lines 113, 114, 123, and 124may be changed in a variety of ways.

Referring to FIG. 19, the second signal line 114 is extended along abottom side of the first insulating substrate 111, and has a second pad114 a, which is adjacent to the first pad 113 a.

Referring to FIG. 20, the fourth signal line 124 is extended along aleft side of the second insulating substrate 121, and has a fourth pad124 a adjacent to the third pad 123 a.

The pads 113 a and 114 a of the first substrate 110 are positioned in apad area K. The pads 123 a and 124 a of the second substrate 120 arepositioned in a pad area J.

According to the present embodiment, the flexible circuit board 400 is asingle sided flexible circuit board. The first flexible circuit board400 a is attached to the first substrate 110 and connected to the firstpad 113 a and the second pad 114 a, and the second flexible circuitboard 400 b is attached to the second substrate 120 and connected to thethird pad 123 a and the fourth pad 124 a.

An exemplary embodiment of the present invention will be described withreference to FIGS. 21 through 25.

Referring to FIG. 21, the flexible circuit board 400 is provided as asingle sided flexible circuit board.

Referring to FIGS. 22 and 23, the pads 113 a, 114 a, 123 a and 124 a areadjacent to each other and the pads 113 a and 114 a of the firstsubstrate 110 overlap with the pads 123 a and 124 a of the secondsubstrate 120. A single pad area M is provided, and thus the flexiblecircuit board 400 may be provided as a single sided flexible circuitboard.

Referring to FIGS. 24A and 24B, the flexible circuit board 400 is adouble sided circuit board and includes four connecting wires.

A first connecting wire includes an input lead 421, an output lead 423,and a lead connecting portion 422 connecting both the leads 421 and 423.A second connecting wire includes an input lead 431, an output lead 433,and a lead connecting portion 432 connecting both the leads 431 and 433.A third connecting wire includes an input lead 441, an output lead 443,and a lead connecting portion 442 connecting both the leads 441 and 443.A fourth connecting wire includes an input lead 451, an output lead 453,and a lead connecting portion 452 connecting both the leads 451 and 453.

The input lead 441 of the third connecting wire and the input lead 451of the fourth connecting wire are positioned on a second surface 411 b.A part of the lead connecting portion 442 of the third connecting wireand a part of the lead connecting portion 452 of the fourth connectingwire are positioned on the second surface 411 b.

The lead connecting portions 422 and 432 positioned on the first surface411 a and the lead connecting portions 442 and 452 positioned on thesecond surface 411 b are connected with each other through a via (notshown) formed on the flexible film 411.

Referring to FIG. 25, the first pad 113 a is electrically connected tothe input lead 451 of the fourth connecting wire through an anisotropicconducting film 500, and the second pad 114 a is electrically connectedto the input lead 441 of the third connecting wire through theanisotropic conducting film 500.

Further, the third pad 123 a is electrically connected to the input lead431 of the second connecting wire, and the fourth pad 124 a iselectrically connected to the input lead 421 of the first connectingwire.

In FIG. 25, the liquid crystal panel 200 under the first insulatingsubstrate 111 is not shown.

According to at least one embodiment of the present invention, the areafor the pads decreases and the number of flexible circuit boards 400decreases.

Double sided flexible circuit boards may be applied to the embodimentsof the present invention where the touch screen panel 100 is separatedfrom the liquid crystal panel 200.

In embodiments of the present invention, the position of the flexiblecircuit board 400 is not limited to an edge area of the touch screenpanel 100. Further, the present invention may be applicable to astructure which includes five or more signal lines. When this occurs,the signal lines may be divided into a group of two signal lines and agroup of three signal lines and then connected to the flexible circuitboard. If the signal lines are more than five, three or more flexiblecircuit boards may be used.

Although the present invention has been described in connection withexemplary embodiments of the present invention, it will be apparent tothose skilled in the art that many variations and modifications may bemade thereto without substantially departing from the scope and spiritof the invention, the scope of which is defined in the appended claimsand their equivalents.

1. A display device comprising: a first substrate which comprises afirst insulating substrate, a first resistance layer formed on the firstinsulating substrate, and first and second signal lines formed on thefirst insulating substrate; a second substrate which faces the firstsubstrate and comprises a second insulating substrate, a secondresistance layer formed on the second insulating substrate, and thirdand fourth signal lines formed on the second insulating substrate; padswhich comprise a first pad connected to the first signal line, a secondpad connected to the second signal line, a third pad connected to thethird signal line, and a fourth pad connected to the fourth signal line;a first flexible circuit board connected to two of the pads; and asecond flexible circuit board connected to the other two of the pads,wherein the pads are formed on the first substrate, and the displaydevice further comprises a conducting member which is formed between thefirst and second substrates and electrically connects the third pad withthe third signal line and the fourth pad with the fourth signal line,respectively.
 2. The display device according to claim 1, wherein thefirst flexible circuit board is connected to one of the first and secondpads and to one of the third and fourth pads.
 3. The display deviceaccording to claim 1, further comprising a liquid crystal panel placedin back of the first substrate.
 4. The display device according to claim3, wherein the first insulating substrate comprises glass, and thesecond insulating substrate comprises a polymer film.
 5. The displaydevice according to claim 3, wherein the liquid crystal panel comprises:a first liquid crystal panel substrate formed with a thin filmtransistor; a second liquid crystal panel substrate facing the firstsubstrate and formed with a black matrix; and a liquid crystal layerpositioned between the first and second liquid crystal panel substrates,and wherein the pads are positioned within an area of the black matrix.6. A display device comprising: a first substrate which comprises afirst insulating substrate, a first resistance layer formed on the firstinsulating substrate, and a plurality of X signal lines formed on thefirst insulating substrate; a second substrate which faces the firstsubstrate and comprises a second insulating substrate, a secondresistance layer formed on the second insulating substrate, and aplurality of Y signal lines formed on the second insulating substrate;pads which comprise a plurality of sub-pads electrically connected toone of the X signal lines and the Y signal lines, respectively; and aflexible circuit board which comprises a flexible film, and a firstinput lead formed on a first surface of the flexible film andcorresponding to a first set of the sub-pads, wherein the firstinsulating substrate comprises glass, the second insulating substratecomprises a polymer film, and the pads are formed on the firstinsulating substrate.
 7. The display device according to claim 6,wherein the sub-pads electrically connected to the X signal line areformed on the first substrate, and the sub-pads electrically connectedto the Y signal line are formed on the second substrate.